Clinical Microbiomics (Denmark)

To diagnose newborn infants with congenital cytomegalovirus (cCMV) related sensorineural hearing loss (SNHL) within the critical four-week window for initiating antiviral treatment, we aimed to determine the number needed to test (NNT) for cCMV among newborn infants failing the neonatal hearing screening. A population-based multicenter cohort study included newborn infants in East Denmark who failed two hearing screening tests and underwent saliva CMV screening between November 2021 and May 2024. The NNT was calculated as the inverse of the absolute detection rate of cCMV-related SNHL in this cohort. A total of 484 infants with hearing screening failure were tested for cCMV. Of these, 27 (5.6%) were CMV positive in saliva and 7 (1.5%) were confirmed to have cCMV in urine, blood, or dried blood spots. Six (85.7%) of 7 infants with cCMV and initial hearing screening failure had normal hearing at follow-up, leaving 1 (0.2%) of 484 with cCMV-related SNHL and an NNT of 484 (95% CI 87-20 000). In our setting, targeted screening for cCMV resulted in a high NNT of almost 500 to identify one newborn infant with cCMV-related SNHL, reflecting a low incidence of cCMV-related SNHL and a high risk of false-positive hearing screening.

ABSTRACT The aim of this study was to obtain insight into the composition and function of the deviant gut microbiome throughout infancy in children born moderately and late preterm and their response to microbiome modulation. We characterized the longitudinal development of the gut microbiome from birth to the age of 12 months by metagenomic sequencing in 43 moderate and late preterm children participating in a randomized, controlled trial (ClinicalTrials.gov/no.NCT00167700) assessing the impact of a probiotic (Lactobacillus rhamnosus GG, ATCC 53,103, currently Lacticaseibacillus rhamnosus GG) and a prebiotic (galacto-oligosaccharide and polydextrose mixture, 1:1) intervention as compared to a placebo administered from 3 to 60 days of life. In addition, 9 full-term, vaginally delivered, breast-fed infants, who remained healthy long-term were included as references. Significant differences in taxonomy, but not in functional potential, were found when comparing the gut microbiome composition of preterm and full-term infants during the first month of life. However, the gut microbiome of preterm infants resembled that of full-term infants by 6 months age. Probiotic and prebiotic treatments were found to mitigate the shift in the microbiome of preterm infants by accelerating Bifidobacteria-dominated gut microbiome in beta diversity analysis. This study provides intriguing information regarding the establishment of the gut microbiome in children born moderately and late preterm, representing the majority of children born preterm. Specific pro- and prebiotics may reverse the proinflammatory gut microbiome composition during the vulnerable period, when the microbiome is low in resilience and susceptible to environmental exposure and simultaneously promotes immunological and metabolic maturation.

Abstract Scavenging indigenous village chickens play a vital role in sub-Saharan Africa, sustaining the livelihood of millions of farmers. These chickens are exposed to vastly different environments and feeds compared to commercial chickens. In this study, we analysed the caecal microbiota of 243 Ethiopian village chickens living in different altitude-dependent agro-ecologies. Differences in bacterial diversity were significantly correlated with differences in specific climate factors, topsoil characteristics, and supplemental diets provided by farmers. Microbiota clustered into 3 enterotypes, with one particularly enriched at high altitudes. We assembled 9,977 taxonomically and functionally diverse metagenome-assembled genomes, the vast majority of which were not found in a dataset of previously published chicken microbes, or in the Genome Taxonomy Database. The wide functional and taxonomic diversity of these microbes highlights their importance in the local adaptation of indigenous poultry, and the significant impacts of environmental factors on the microbiota argues for further discoveries in other agro-ecologies.

Oligosaccharides in human milk support health via intestinal microbiome. We studied effects of addition of 2-fucosyllactose (2′FL) to the infant formula on infant growth, occurrence of adverse events (AE), and infant microbiome, including expression of microbial genes that metabolize 2′FL. Our hypothesis was that while 2′FL would not affect growth, it would cause changes in microbiome metabolism. In a double-blinded randomized controlled study fashion, the infant formula ± 2′FL or human milk was fed to healthy term infants for 16 weeks. Fecal samples obtained at baseline and week 16 were analyzed for microbial populations, metagenomic species concept (MGS), and genetics of gut metabolic modules (GMMs). There were no effects of addition of 2′FL on growth or AEs. There were no significant differences by feeding group in MGS richness or Shannon diversity at baseline, but formula groups each had significantly greater richness (p < 0.05) and diversity (p < 0.05) after 16 weeks of feeding than the breastfed group. While two glycosyl hydrolase (GH) families (GH42 and GH112) were significantly increased, two other GH families (GH20 and GH2) were significantly decreased in the test formula group compared to the control formula group; although modest, addition of 2′FL resulted in changes in microbiome in the direction of breastfed infants, consistent with internal metabolism of HMOs by Bifidobacterium.

This open-label, non-randomized, multicenter trial (Registration: NCT 03661736) aimed to assess if an amino acid-based formula (AAF) supplemented with two human milk oligosaccharides (HMO) supports normal growth and is well tolerated in infants with a cow’s milk protein allergy (CMPA). Term infants aged 1–8 months with moderate-to-severe CMPA were enrolled. The study formula was an AAF supplemented with 2′-fucosyllactose (2′-FL) and lacto-N-neotetraose (LNnT). Infants were fed the study formula for 4 months and were offered to remain on the formula until 12 months of age. Tolerance and safety were assessed throughout the trial. Out of 32 infants (mean age 18.6 weeks; 20 (62.5%) male), 29 completed the trial. During the 4-month principal study period, the mean weight-for-age Z score (WAZ) increased from –0.31 at the baseline to +0.28 at the 4-months’ follow-up. Linear and head growth also progressed along the WHO child growth reference, with a similar small upward trend. The formula was well tolerated and had an excellent safety profile. When comparing the microbiome at the baseline to the subsequent visits, there was a significant on-treatment enrichment in HMO-utilizing bifidobacteria, which was associated with a significant increase in fecal short-chain fatty acids. In addition, we observed a significant reduction in the abundance of fecal Proteobacteria, suggesting that the HMO-supplemented study formula partially corrected the gut microbial dysbiosis in infants with CMPA.

Accumulating evidence supports the findings of an altered gut microbiota in patients with autoimmune disease. However, existing studies on the role of the gut microbiota in patients with psoriasis have demonstrated conflicting results and have mainly been based on 16s rRNA gene sequencing analysis. To examine whether the gut microbiota of patients with psoriasis was altered in composition and functional potentials compared with healthy controls, and as a second approach compared with healthy cohabitant partners. A further aim was to investigate relationships to disease severity, and seasonal impact on the gut microbiota. In a case-control study, 126 faecal samples were collected from a sample of 53 systemically untreated patients with plaque psoriasis; 52 healthy controls matched for age, sex and body mass index; and 21 cohabitant partners. A subpopulation of 18 patients with psoriasis and 19 healthy controls continued in a longitudinal study, where four to six faecal samples were collected over 9-12 months. The gut microbiota was characterized using shotgun metagenomic sequencing analysis. A significantly lower richness (P = 0·007) and difference in community composition (P = 0·01) of metagenomic species was seen in patients with psoriasis compared with healthy controls, and patients with psoriasis had a lower microbial diversity than their partners (P = 0·04). Additionally, the functional richness was decreased in patients with psoriasis compared with healthy controls (P = 0·01) and partners (P = 0·05). Increased disease severity was correlated with alterations in taxonomy and function, with a slight tendency towards a lower richness of metagenomic species, albeit not significant (P = 0·08). The seasonal analysis showed no shifts in community composition in healthy controls or in patients with psoriasis. The findings of a different gut microbiota in composition and functional potentials between patients with psoriasis and healthy controls support a linkage between the gut microbiota and psoriasis. These findings need to be validated in larger studies, and a potential causal relationship between the gut microbiota and psoriasis still needs to be shown.

Abstract Background: Despite the discovery of familial cases with mutations in Cu/Zn-superoxide dismutase (SOD1), Guanine nucleotide exchange C9orf72, TAR DNA-binding protein 43 (TARDBP) and RNA-binding protein FUS as well as a number of other genes linked to Amyotrophic Lateral Sclerosis (ALS), the etiology and molecular pathogenesis of this devastating disease is still not understood. As proteins do not act alone, conducting an analysis of ALS at the system level may provide new insights into the molecular biology of ALS and put it into relationship to other neurological diseases.Methods: A set of ALS-associated genes/proteins were collected from publicly available databases and text mining of scientific literature. We used these as seed proteins to build protein-protein interaction (PPI) networks serving as a scaffold for further analyses. From the collection of networks, a set of core modules enriched in seed proteins were identified. The molecular biology of the core modules was investigated, as were their associations to other diseases. To assess the core modules’ ability to describe unknown or less well-studied ALS biology, they were queried for proteins more recently associated to ALS and not involved in the primary analysis.Results: We describe a set of 26 ALS core modules enriched in ALS-associated proteins. We show that these ALS core modules not only capture most of the current knowledge about ALS, but they also allow us to suggest biological interdependencies. In addition, new associations of ALS networks with other neurodegenerative diseases, e.g. Alzheimer’s, Huntington’s and Parkinson’s disease were found. A follow-up analysis of 140 ALS-associated proteins identified since 2014 reveals a significant overrepresentation of new ALS proteins in these 26 disease modules.Conclusions: Using protein-protein interaction networks offers a relevant approach for broadening the understanding of the biological context of known ALS-associated genes. Using a bottom-up approach for the analysis of protein-protein interaction networks is a useful method to avoid bias caused by over-connected proteins. Our ALS-enriched modules cover most known biological functions associated with ALS. The presence of recently identified ALS-associated proteins in the core modules highlights the potential for using these as a scaffold for identification of novel ALS disease mechanisms.

SummaryBackground and ObjectivesEarly life is a critical window for adiposity programming. Metabolic‐profile in early life may reflect this programming and correlate with later life adiposity. We investigated if metabolic‐profile at 3 months of age is predictive for body composition at 2 years and if there are differences between boys and girls and between infant feeding types.MethodsIn 318 healthy term‐born infants, we determined body composition with skinfold measurements and abdominal ultrasound at 3 months and 2 years of age. High‐throughput‐metabolic‐profiling was performed on 3‐month‐blood‐samples. Using random‐forest‐machine‐learning‐models, we studied if the metabolic‐profile at 3 months can predict body composition outcomes at 2 years of age.ResultsPlasma metabolite‐profile at 3 months was found to predict body composition at 2 years, based on truncal: peripheral‐fat‐skinfold‐ratio (T:P‐ratio), with a predictive value of 75.8%, sensitivity of 100% and specificity of 50%. Predictive value was higher in boys (Q2 = 0.322) than girls (Q2 = 0.117). Of the 15 metabolite variables most strongly associated with T:P‐ratio, 11 were also associated with visceral fat at 2 years of age.ConclusionSeveral plasma metabolites (LysoPC(22:2), dimethylarginine and others) at 3 months associate with body composition outcome at 2 years. These results highlight the importance of the first months of life for adiposity programming.

Low diversity intestinal dysbiosis has been associated with inflammatory bowel disease, including patients with ulcerative colitis with an ileo-anal pouch anastomosis. Furthermore, specific Escherichia coli phylogroups have been linked to inflammatory bowel disease. Our aim was to characterize the differences among microbiota and E. coli phylogroups in active and inactive pouchitis. Disease activity was assessed using the modified pouch disease activity index and by fecal calprotectin. Microbiota diversity was assessed by 16S rDNA MiSeq sequencing. E. coli phylogroup was determined after triplex PCR. Twenty patients with ulcerative colitis with an ileo-anal pouch anastomosis were included, 10 of whom had active pouchitis. Ileo-anal pouch anastomosis patients had an increased abundance of Proteobacteria colonization compared to patients with ulcerative colitis or Crohn’s disease and healthy controls, p = 1.4·10−5. No differences in E. coli phylogroup colonization could be determined between cases of active and inactive disease. No significant link was found between α-diversity and pouch inflammation. However, higher levels of Fusobacteria colonization were found in patients with a pouch with a fecal calprotectin level above 500, p = 0.02. In conclusion, patients with a pouch had an increased Proteobacteria abundance, but only Fusobacteria abundance was linked to inflammation.